共查询到20条相似文献,搜索用时 28 毫秒
1.
Roland Wolff 《Integral Equations and Operator Theory》2000,38(1):120-127
In this paper, we prove that the Hardy spaceH
p
(), 1p<, over a strictly pseudoconvex domain in
n
with smooth boundary is quasi-coherent. More precisely, we show that Toeplitz tuplesT
with suitable symbols onH
p
() have property (). This proof is based on a well known exactness result for the tangential Cauchy-Riemann complex. 相似文献
2.
A model of taxation for cooperativen-person games is introduced where proper coalitions Are taxed proportionally to their value. Games with non-empty core under taxation at rate-balanced. Sharp bounds on in matching games (not necessarily bipartite) graphs are estabLished. Upper and lower bounds on the smallest in bin packing games are derived and euclidean random TSP games are seen to be, with high probability,-balanced for0.06. 相似文献
3.
J. C. Liu 《Journal of Optimization Theory and Applications》1991,69(1):153-167
Necessary Kuhn-Tucker conditions up to precision without constraint qualification for -Pareto optimality of multiobjective programming are derived. This article suggests the establishment of a Wolfe-type -duality theorem for nondifferentiable, nonconvex, multiobjective minimization problems. The -vector Lagrangian and the generalized -saddle point for Pareto optimality are studied. 相似文献
4.
Jiří Matoušek 《Discrete and Computational Geometry》1990,5(1):427-448
LetS be a set ofn points in the plane and let be a real number, 0<<1. We give a deterministic algorithm, which in timeO(n
–2 log(1/)+
–8) (resp.O(n
–2 log(1/)+
–10) constructs an-netNS of sizeO((1/) (log(1/))2) for intersections ofS with double wedges (resp. triangles); this means that any double wedge (resp. triangle) containing more thatn points ofS contains a point ofN. This givesO(n logn) deterministic preprocessing for the simplex range-counting algorithm of Haussler and Welzl [HW] (in the plane).We also prove that given a setL ofn lines in the plane, we can cut the plane intoO(
–2) triangles in such a way that no triangle is intersected by more thann lines ofL. We give a deterministic algorithm for this with running timeO(n
–2 log(1/)). This has numerous applications in various computational geometry problems. 相似文献
5.
S. V. Petras 《Journal of Mathematical Sciences》1984,24(3):380-386
The behavior of the poles zn(), n=1,2,... of the scattering matrix of the operatorl
u=–u(x), x , (u/n)+(x)u|=0 as 0 is considered. It is proved that |zn()–zn|=0((1/2)qn), where qn is the order of the pole of the scattering matrix for the operator 0u=–u, u/=0.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 117, pp. 183–191, 1981. 相似文献
6.
Otto Röschel 《Journal of Geometry》1992,44(1-2):160-170
We study a map of osculating elements of an affine Cayley- Klein (CK-) plane into the Lie algebraA
4(2) of the aequiform transformationsA
4(2) of the given plane. If we use the real projective spaceP
3() overA
4(2) each osculating element defines a straight line inP
3(). In the first part of this paper this map is studied in detail. In the second part we study second order properties of one- parameter motions and their corresponding properties in the Lie algebraA
4(2). This is done by considering the analogen to the formula of EULERSAVARY in the image spaceP
3() overA
4(2). 相似文献
7.
V. G. Sushko 《Mathematical Notes》1970,8(3):646-652
The proximity is investigated of the solution of Cauchy's problem for the equation u
t
+((u))x= u
xx
((u) > 0) to the solution of Cauchy's problem for the equation ut+ ((u))x= 0, when the solution of the latter problem has a finite number of lines of discontinuity in the strip 0 t T. It is proved that, everywhere outside a fixed neighborhood of the lines of discontinuity, we have |u–u| C, where the constant C is independent of. Similar inequalities are derived for the first derivatives of u–u.Translated from Matematicheskie Zametki, Vol. 8, No. 3, pp. 309–320, September, 1970.In conclusion we express our gratitude to L. A. Chudov for his valuable advice concerning this work. 相似文献
8.
We find the asymptotic behavior of the Jost function(Z,) of a two-dimensional Schrödinger operator for arbitrary and Z/|Z|S1 as |Z| We discuss consequences of the asymptotic formulas for the inverse scattering problem.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 173, pp. 96—103, 1988. 相似文献
9.
Given a point-to-set operator T, we introduce the operator T defined as T(x)= {u: u – v, x – y – for all y Rn, v T(y)}. When T is maximal monotone T inherits most properties of the -subdifferential, e.g. it is bounded on bounded sets, T(x) contains the image through T of a sufficiently small ball around x, etc. We prove these and other relevant properties of T, and apply it to generate an inexact proximal point method with generalized distances for variational inequalities, whose subproblems consist of solving problems of the form 0 H(x), while the subproblems of the exact method are of the form 0 H(x). If k is the coefficient used in the kth iteration and the k's are summable, then the sequence generated by the inexact algorithm is still convergent to a solution of the original problem. If the original operator is well behaved enough, then the solution set of each subproblem contains a ball around the exact solution, and so each subproblem can be finitely solved. 相似文献
10.
Karl-Heinz Förster 《manuscripta mathematica》1969,1(1):1-7
For a bounded linear operator T in a Hilbert space denote by (T) the set of the extreme points of its numerical range W(T), and by K(T) the subset of the points of (T) which lie on the boundary of a disc being a spectral set for T in the sense of J. von Neumann. Each corner of W(T) belongs to K(T). This implies: K(T) is dense in (T) if T is compact and the convex hull of its spectrum contains W(T). If Re T0 and o (T) then a necessary and sufficient condition is given that O is a eigenvalue of T. This is applied to show that W(T) (T) is a subset of the point spectrum of T for a class of operators containing the hyponormal operators. 相似文献
11.
A model spectral problem of the form -i)y+xy= y on the finite interval [-1,1] with the Dirichlet boundary conditions is considered. Here is the spectral parameter and is positive. The behavior of the spectrum of this problem as 0 is completely investigated. The limit curves are found to which the eigenvalues concentrate and the counting eigenvalue functions along these curves are obtained. 相似文献
12.
A. Yu. Solynin 《Journal of Mathematical Sciences》2001,105(4):2220-2234
Let D be a simply connected domain on the complex plane such that 0 D. For r > 0 , let D
r be the connected component of D {z : |z| < r} containing the origin. For fixed r, we solve the problem on minimization of the conformal radius R(D
r, 0) among all domains D with given conformal radius R(D, 0). This also leads to the solution of the problem on maximization of the logarithmic capacity of the local -extension E
(a) of E among all continua E with given logarithmic capacity. Here, E
(a) = E {z : |z – a| }, a E, > 0. Bibliography: 12 titles. 相似文献
13.
One considers the differential equation dx/dt=f(t, x) with the impulse action ¦t=ti=Hi(ti,x) in the space of bounded numerical sequences, where f(t, x), Hi(t, x) are T-periodic, countable-dimensional vector-valued functions, is a positive parameter. One gives conditions for the existence of a control (1,2) such that the solution of the equation dx/dt=f(t, x)–1 with impulse action x¦t=ti=Hi(ti,x)–2 assuming for t= the value x=x0, be T-periodic.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 2, pp. 271–275, February, 1990. 相似文献
14.
L. Chierchia C. Falcolini 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1996,47(2):210-220
We extend a recent method of proof of a theorem by Kolmogorov on the conservation of quasi-periodic motion in Hamiltonian systems so as to prove existence of (uncountably many) real-analytic quasi-periodic solutions for elliptic systems u=f
x
(u, y), whereu y
M
u(y)
N
,f=f(x, y) is a real-analytic periodic function and is a small parameter. Kolmogorov's theorem is obtained (in a special case) whenM=1 while the caseN=1 is (a special case of) a theorem by J. Moser on minimal foliations of codimension 1 on a torusT
M
+1. In the autonomous case,f=f(x), the above result holds for any . 相似文献
15.
We consider the boundary-value problem u
tt + u
t + (1 + cos2)sin u =2
u
xx, u
x|x=0=ux|x==0, where 0<1, =(1+)t, ,> 0, and the sign of is arbitrary. It is proved that for an appropriate choice of the external parameters and and for sufficiently small the number of exponentially stable solutions 2-periodic in can be made equal to an arbitrary predefined number. 相似文献
16.
S. A. Aldashev 《Ukrainian Mathematical Journal》1993,45(9):1456-1464
It is proved that multi-dimensional Darboux problems for the wave equation are correct in the domain
bounded by the surfaces ¦x ¦=t + and ¦x ¦=1- t and the planet = 0, 0 < 1. The behavior of the solutions as 0 is studied.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 9, pp. 1299–1306, September, 1993. 相似文献
17.
Klaus Wendler 《Mathematical Methods of Operations Research》1971,15(1):1-14
Zusammenfassung Durch eine -Störung in der Diagonalen der quadratischen Form kann man eine lineare oder quadratisch semidefinite Optimierungsaufgabe zu einer streng definiten quadratischen Aufgabe machen, so daß Lösungsverfahren, die die Formmatrix als nichtsingulär voraussetzen müssen, anwendbar werden. Bekanntlich konvergiert die Lösungx
der -gestörten Aufgabe für 0 gegen den Lösungsvektorx
m von minimalem Betrag der ursprünglichen Aufgabe. Wir zeigen darüber hinaus, daß im linearen Fall immer und im eigentlich quadratischen in gewissen Fällen schon für 0<<* die beiden Lösungenx
undx
m übereinstimmen. Im linearen Fall ist die obere Grenze * durch die Lösung eines linearen Ungleichungssystems gegeben.Im zweiten Abschnitt wenden wir dasHildreth-Verfahren mittels der -Störung auf lineare und quadratisch semidefinite Aufgaben an, diskutieren Konvergenz- und Genauigkeitsfragen und kommen zu dem Schluß, daß man in der Praxis sowohl bei Rechnung von Hand als auch bei maschineller Rechnung zu befriedigenden Ergebnissen kommt.
Der Verfasser ist Herrn Prof. Dr.W. Vogel, Bonn, für einen Hinweis zu Dank verpflichtet.
Vorgel. v.:H. P. Künzi 相似文献
Summary Linear and quadratic semidefinite programming problems may be transformed into strongly definite quadratic problems by means of an -perturbation of the quadratic form so that procedures which presuppose the matrix of the form to be nonsingular, may be applied. As is well known, the solutionx of the -perturbated problem converges to the solutionx m of minimal length of the original problem as 0. We show that always in the linear case and in the quadratic case under certain circumstances, both solutionsx andx m are equal if 0 <<*. In the linear case, the upper limit * is given by the solution of a system of linear inequalities.In the second part of this paper we apply the method ofHildreth to linear and quadratic semidefinite programming problems by the -perturbation. We discuss questions of convergence and exactness, and conclude that in practice calculation by hand as well as by computer leads to satisfying results.
Der Verfasser ist Herrn Prof. Dr.W. Vogel, Bonn, für einen Hinweis zu Dank verpflichtet.
Vorgel. v.:H. P. Künzi 相似文献
18.
We establish conditions necessary for -controllability in dimension one of first-order singular linear differential equation in Banach spaces. This result generalizes similar results for regular equations. For this class of equations, we show that the notion of -controllability in dimension two is more natural, and moreover, analogous necessary conditions are sufficient in the case of dimension two. Using an abstract approach, we derive sufficient conditions for the -controllability in dimension two of the Cauchy--Dirichlet problem for the Barenblatt--Zheltov--Kochina equation. 相似文献
19.
Ralph-Hardo Schulz 《Journal of Geometry》1986,26(2):186-190
We prove: Let G be a finite group with a non-trivial partition (G) and a set (G) of subgroups such that any two components of (G) are contained in at least one W with W (G) and W G; then G is a p-group or a Frobenius group.From this we obtain: A finite group with a linear partition can only be an abelian p-group or a Frobenius group.Dedicated to Prof. H. Lenz on the occasion of his 70th birthday 相似文献
20.
S. A. Vakulenko 《Journal of Mathematical Sciences》1982,20(1):1800-1806
A problem with periodic boundary conditions is considered for the Fock-Klein-Gordon equation perturbed by a small nonlinear operator R[t, u, ux, uxx]:. It is shown that under certain conditions the solution exists and is close to the known asymptotic solution on the interval 0 t l/.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 104, pp. 84–92, 1981.In conclusion, the author wishes to thank I. A. Molotkov, V. M. Babich, Ya. V. Kurylev, M. M. Popov, V. B. Filippov, and all the participants in the seminar on wave diffraction (LOMI) for valuable advice, pointers, and discussions. 相似文献